Create a seperate folder for the driver and install the driver file into it. After creating the folder, use the 'change display adapter' option under display adapter properties. Use the browse feature to point the file path to the drver folder you created. Then restart.
This is the only S3 driver I have found so far that works with my AGP S3 Trio 3D card, and according to the site I got it from it works equally well with PCI cards as well. If you have any problems installing it e mail me for more comprehensive instructions.